Composite metal article



March 10, 1936. w. BROWN COMPOSITE METAL ARTICLE Filed May 27, 1929INVENTOR ATTORNEYS an... Mar. 16, i936 UNITED STATES PATENT OFFICE2,033,814 COMPOSITE METAL ARTICLE Walter Brown, Toledo, Ohio ApplicationMay 27, 1929, Serial No. 366,468

13 Claims. (oi. est-.461)

The invention relates to the manufacture of composite metal articlescomposed of two different metals or alloys integrally and continuouslybonded together. More particularly the invention relates to certainarticles of manufacture requiring different properties in differentportions thereof, thus making the use of two'dlfferent alloys desirablefor the manufacture of the same. For example, a valve seat bushing foroil wells can be constructed in accordance with The .inner alloy must beintegrally bonded to the outer tube and it is therefore preferable toutilize the process outlined in my co-pending epplication (Patent No.1,923,075) filed on even date herewith. This process briefly describedconsists in placing the desired amount of the solid alloy within a tubeof steel or other tough alloy and after closing the ends thereofsubjecting the same to a temperature sumcient to melt the alloy but notthe outer tube; The tube is then rotated at a speed such that the moltenalloy forms a pool at the bottom. of the tube and washes the sides ofthe tube removing. foreign matter therefrom which might otherwiseinterfere with the formation of a proper bond. After sufficient washingaction the tube'is cooled down while the rotation continues untilfinally the alloy congeals and forms a solid ring uniformly spaced fromthe axis of rotation and integrally and continuously bonded to the outermetal. The alloy is thus centrifugally cast to the inner surface of theouter tube. With certain metals and alloys it is desirable to increasethe speed of rotation after the initial washing action so that the metalis evenly distributed around the tube at the time when solidificationoccurs.

In the drawing,

Figure 1 is an axial section through an ollwell,

bushing;

Figure 2 is a cross section thereof. I he oil well bushing comprises anouter ring III formed of steel or other tough alloy having an annularrib H on the periphery thereof. Integrally and continuously joinedthereto is the inner ring i2 formed of a hard, wear-resisting alloypreferably comprising chromium and a metal of the class consisting ofcobalt and nickel. The inner ring is of uniform diameter and has thebeveled edge I3 at one or both ends thereof 5 forming the seat for thevalve.

Another composition for the inner ring is as follows:

' Approximate percentage Cobalt 50 10 Chromium 32 Tungsten 16"Molybdenum 2 The above alloys have a fusing point of approximately 2350to 2400 degrees F., whereas the m melting point of ordinary steel isapproximate] 2800 degrees F. or above.

My invention also contemplates articles other than the oil well bushingabove described. Thus, there are many-other devices wherein an outertube of a relatively tough alloy may be advantageously associated withan integrally bonded inner lining of a metal or alloy having arelatively high fusing point. Another example of my 25 invention is asteel or other alloy tube having an inner lining of bronze. A tube ofthis character may be used for bearings and is superior to an all bronzebearing bushing because the'latter has a different coefficient ofexpansion than the steel, 30 whereas in my improved bushing thecoefficient of expansion is substantially the same as steel because thesteel constitutes the major part of the article. In carrying out myinvention it is essential that the high fusing inner. metal be 35integrally and continuously bonded to the outer material. By this it ismeant that the lining has characteristics resulting from the fact thatit has been solidified from the molten condition simultaneously over theentire surface. In view 40 of the fact that the melting temperature ofthe inner alloy is relatively high, extreme care must be exercised toprevent such oxidation of the metal as would prevent the formation ofthe proper bond. One process adapted for the i'nanu- 45 facture of thearticles herein described and claimed is set forth in my Patent No.1,923,075.

What I claim as my invention is:

1. A valve seat bushing comprising an outer tube of steel and acentrifugally cast inner tube 50 integrally and continuously bondedthereto composed of a hard.- wear-resisting non-ferrous alloy containingchromium and a metal of the class consisting of cobalt and nickel. u

3. A valve. seat bushing comprising an outen metallic ring having anannular rib extending radially outward from the periphery thereof and acentrifugally cast inner lining integrally and continuously bondedthereto having approximately the following composition:

Per cent Cobalt 50 Chromium 32 Iungsten 16 Molybdenum I 2 4. As anarticle of manufacture, an outer metallic tube,.an inner metallic liningintegrally and continuously bonded thereto, the inner lining comprisinga metal having a melting point over 1000 F. and the outer member being apreformed tube of a metal having a melting point substantially higherthan the melting point of the inner lining.

5. As an article of manufacture, a preformed outer tube and acentrifugally cast metallic inner lining continuously bonded thereto,said lining being of a metal having a melting point above 1000 F. andsaid outer tube being of a metal having a melting point substantiallyabove the melting point of said inner metal. v

6. A valve seat bushing comprising an outer steel tube and acentrifugally cast inner tube integrally and continuously bonded theretocomposed ofa non-ferrous alloy containing chromium, tungsten and a metalof the class consisting of cobalt and nickel, said steel tube having anannular rib extending radially outward from the outer surface thereofand said inner tube having a bevel edge forming a valve seat.

'7. As an article of manufacture, a preformed outer tube and acentrifugally cast metallic inner lining, said lining being of a metalhaving a melting point above 1000 F. and having ametallic structurecharacteristic of centrifugal'ly cast metal, said outer tube being of ametal having a melting point substantially above the melting point ofsaid inner metal, said inner metal being 9. As an article ofmanufacture, a preformed outer tube and a centrifually cast metallicinner lining continuously bonded thereto, said lining being of a hardwear-resisting metal having a melting point above 1000' F. and saidouter tube being of steel having a. melting point substantially abovethe melting point of said inner metal.

10. As an article of manufacture, a preformed outer steel tube and acentrifugally cast bronze inner lining continuously bonded thereto, saidbronze lining having a melting point above 1000 F. and said steel outertube having a melting point substantially above the melting point ofsaid bronze lining.

11. As an article of manufacture, a preformed metallic tube, acentrifugally cast metallic layer integrally and continuously bondedthereto, the centrifugally cast metallic layer having a melting pointabove 1000 F. and the preformed metallic tube having a melting pointsubstantially above the melting point of said centrifugally castmetallic layer.

12. As an article of manufacture, a preformed metallic tube, acentrifugally cast metallic layer integrally and continuously bondedthereto, the centrifugally cast metallic layer being of a. hardwear-resisting metal having a melting point above 1000 F. and saidpreformed tube being of steel having a melting point substantially abovethe melting point of said hard wear-resisting metal.

13. As an article of manufacture, a preformed metallic tube, acentrifugally cast metallic layer integrally and continuously bondedthereto, the centrifugally cast layer being of bronze having a meltingpoint above 1000 F. and said preformed tube being of steel having a.melting point substantially above the melting point of said bronze.

' WALTER BROWN-

